Process for preparation of monocyclopentadienyl metal complex compounds and method of use

ABSTRACT

Cationic Group 4 or Lanthanide metal catalysts containing a single, delocalized π-bonded group are prepared by contacting a metal complex with a carbonium salt of a compatible, non-coordinating anion.

CROSS-REFERENCE TO RELATED APPLICATION

This is a divisional of application Ser. No. 07/884,966, filed May 15,1992, now U.S. Pat. No. 5,350,723.

BACKGROUND OF THE INVENTION

This invention relates to a method for preparing compositions of matterthat are useful as catalysts, and to a method of using these catalystsfor polymerizing addition polymerizable monomers. More particularly thepresent invention relates to an improved method for preparing a class ofcatalysts known as constrained geometry catalysts.

In U.S. Ser. No. 545,403, filed Jul. 3, 1990, (published in equivalentform 3/13/91 as EP-A-416,815) there are disclosed certain constrainedgeometry metal complexes and catalysts derived by reacting the metalcomplex with activating cocatalysts. In U.S. Pat. 5,064,802 (published3/20/91 in equivalent form as EP-A-418,044) there are disclosed certainfurther constrained geometry metal catalysts formed by reacting suchmetal complexes with salts of Bronsted acids containing anoncoordinating compatible anion. The reference discloses the fact thatsuch complexes are usefully employed as catalysts in additionpolymerizations. In U.S. Ser. No. 720,041, filed Jun. 24, 1991, nowabandoned an alternative technique for preparing cationic constrainedgeometry catalysts by anion abstraction using borane compounds isdisclosed. For the teachings contained therein, the foregoing UnitedStates patent and applications are herein incorporated by reference.

It has been previously known in the art to employ carbonium, oxonium orsulfonium ions to generate cationic bis-cyclopentadienyl Group 4 metalcatalysts. Such a process is disclosed in EP-A2 426,637 published May 8,1991.

It would be desirable if there were provided an improved method thatwould allow the production of even more efficient catalysts as well asan improved addition polymerization process utilizing such catalysts.

SUMMARY OF THE INVENTION

As a result of investigations carried out by the present inventors thereis now discovered a new and improved method for the preparation ofcatalysts and an improved method for polymerization of additionpolymerizable monomers.

In accordance with the present invention there is provided a process forpreparing a cationic complex having a limiting charge separatedstructure corresponding to the formula:

    LMX.sub.m X'.sub.n X".sub.p.sup.+ A.sup.-

wherein:

L is a single, delocalized π-bonded group that is bound to M, containingup to 50 nonhydrogen atoms;

M is a metal of Group 4 or the Lanthanide series of the Periodic Tableof the Elements;

X is a divalent substituent of up to 50 non-hydrogen atoms that togetherwith L forms a metallocycle with M that imparts a constrained geometryto the metal active site;

X' is a neutral Lewis base ligand having up to 20 non-hydrogen atoms;

m and n are independently zero or one;

X" each occurrence is a monovalent moiety selected from hydride, halo,alkyl, aryl, silyl, germyl, aryloxy, alkoxy, amide, siloxy, andcombinations thereof (e.g. haloalkyl, haloaryl, halosilyl, alkaryl,aralkyl, silylalkyl, aryloxyaryl, alkyoxyalkyl, amidoalkyl, amidoaryl,etc.) having up to 20 non-hydrogen atoms;

p is an integer equal to M-m-2, where M is the valence of M; and

A⁻ is noncoordinating, compatible anion;

the steps of the process comprising contacting:

a) a derivative of a Group 4 or Lanthanide metal corresponding to theformula:

    LMX.sub.m X'.sub.n X".sub.p+1

wherein

L, M, X, m, X', n, X", and p are as previously defined, with

b) a salt corresponding to the formula: ©+A-, wherein ©+ is a stable,carbonium ion containing up to 30 nonhydrogen atoms and A- is aspreviously defined;

under conditions to cause abstraction of one X" and formation of theneutral species, ©X".

Such cationic complexes formed in the present invention are usefullyemployed in addition polymerization processes to prepare polymers,especially olefin polymers, for use in molding, film, sheet, extrusionfoaming and other applications. Accordingly, a further embodiment of thepresent invention is a catalyzed addition polymerization processcharacterized in that the addition polymerization catalyst is a cationiccomplex formed according to the above process.

DETAILED DESCRIPTION

All reference to the Periodic Table of the Elements herein shall referto the Periodic Table of the Elements, published and copyrighted by CRCPress, Inc., 1989. Also, any reference to a Group or Groups shall be tothe Group or Groups as reflected in this Periodic Table of the Elementsusing the IUPAC system for numbering groups.

The term "carbonium ion" refers to cationic species that possess anelectron deficient tri-coordinant carbon atom. Such ions are alsoreferred to in the art as carbenium ions. Stable carbonium ions are suchcationic species that are able to exist in solution withoutdecomposition for a time period sufficient to undergo the reactionsdesired of the present invention. Preferred carbonium ions are thoseions that are incapable of coordination with the metal atom or metalcomplex. Examples include tropylium (cycloheptatrienylium), trityl(triphenylmethylium), benzene(diazonium) ions.

As used herein, the recitation "noncoordinating, compatible anion" meansan anion which either does not coordinate to the metal containingportion of the complex or which is only weakly coordinated theretothereby remaining sufficiently labile to be displaced by a neutral Lewisbase. A noncoordinating, compatible anion specifically refers to acompatible anion which, within the time frame of the desired end use,when functioning as a charge balancing anion in the catalyst system ofthis invention does not transfer an anionic substituent or fragmentthereof to said cation thereby forming a neutral four coordinate metalcomplex and a neutral metal byproduct. "Compatible anions" are alsoanions that are not degraded to neutrality when the initially formedcomplex decomposes and that are noninterfering with the desiredsubsequent polymerization or other uses of the complex.

More particularly the noncoordinating, compatible anion may comprise asingle coordination complex comprising a charge-bearing metal ormetalloid core, which anion is both bulky and non-nucleophilic. Therecitation "metalloid", as used herein, includes non-metals such asboron, phosphorus and the like which exhibit semi-metalliccharacteristics.

Preferably according to the present invention, there is provided aprocess for preparing a cationic complex having the foregoing, limiting,charge separated, structure wherein:

L is a single, delocalized π-bonded group that is bound to M, containingup to 50 nonhydrogen atoms;

M is a metal of Group 4 or the Lanthanide series of the Periodic Tableof the Elements;

X is a divalent substituent of up to 50 non-hydrogen atoms that togetherwith L forms a metallocycle with M that imparts a constrained geometryto the metal active site;

m is one;

X' is a neutral Lewis base ligand having up to 20 non-hydrogen atoms;

n is zero or one;

X" each occurrence is a monovalent moiety selected from hydride, halo,alkyl, aryl, silyl, germyl, aryloxy, alkoxy, amide, siloxy, andcombinations thereof (e.g. haloalkyl, haloaryl, halosilyl, alkaryl,aralkyl, silylalkyl, aryloxyaryl, alkyoxyalkyl, amidoalkyl, amidoaryl,etc.) having up to 20 non-hydrogen atoms;

p is an integer equal to M-3, where M is the valence of M; and

A⁻ is noncoordinating, compatible anion,

the steps of the process comprising contacting:

a) a derivative of a Group 4 or Lanthanide metal corresponding to theformula:

    LMXX'.sub.n X".sub.p+1

wherein

L, M, X, X', n, X", and p are as previously defined; with

b) a salt corresponding to the formula: ©+A-, wherein ©+ is a stable,carbonium ion containing up to 30 nonhydrogen atoms and A- is aspreviously defined;

under conditions to cause abstraction of one X" and formation of theneutral species, ©X".

By use of the term "constrained geometry" herein is meant that the metalatom is forced to greater exposure of the active metal site because oneor more substituents on the substituted delocalized π-bonded group formsa portion of a ring structure including the metal atom, wherein themetal is both bonded to an adjacent covalent moiety and held inassociation with the substituted delocalized π-bonded group through anη⁵ or other π-bonding interaction. It is understood that each respectivebond between the metal atom and the constituent atoms of the substituteddelocalized π-bonded group need not be equivalent. That is, the metalmay be symmetrically or unsymmetrically π-bound to the substituteddelocalized π-bonded group.

The geometry of the active metal site is further defined as follows. Thecenter of the substituted delocalized π-bonded group may be defined asthe average of the respective X, Y, and Z coordinates of the atomiccenters forming the substituted delocalized π-bonded group. The angle, ,formed at the metal center between the center of the ligating atom ofeach other ligand of the metal complex may be easily calculated bystandard techniques of single crystal X-ray diffraction. Each of theseangles may increase or decrease depending on the molecular structure ofthe constrained geometry metal complex. Those complexes wherein one ormore of the angles, , is less than in a similar, comparative complexdiffering only in the fact that the constrain-inducing substituent isreplaced by hydrogen have constrained geometry for purposes of thepresent invention. Preferably one or more of the above angles, ,decrease by at least 5 percent, more preferably 7.5 percent, compared tothe comparative complex. Highly preferably, the average value of allbond angles, , is also less than in the comparative complex.

Preferably, cationic complexes of Group 4 or Lanthanide metals preparedaccording to the present invention have constrained geometry such thatthe smallest angle, , is less than 115°, more preferably less than 110°.

Substituted, delocalized π-bonded groups for use herein include anyπ-electron containing moiety capable of forming a delocalized bond withthe Group 4 or Lanthanide metal and further substituted with a divalentsubstituent that is also covalently bound to the metal. Divalentsubstituents preferably include groups containing up to 30 nonhydrogenatoms comprising at least one atom that is oxygen, sulfur, boron or amember of Group 14 of the Periodic Table of the Elements directlyattached to the delocalized π-bonded group, and a different atom,selected from the group consisting of nitrogen, phosphorus, oxygen orsulfur that is covalently bonded to M. Examples of suitable delocalized,π-bonded groups are cyclopentadienyl- or allyl-groups, and derivativesthereof.

By the term "derivative" when used to describe the above substituted,delocalized π-bonded groups is meant that each atom in the delocalizedπ-bonded group may independently be substituted with a radical selectedfrom the group consisting of hydrocarbyl radicals,substituted-hydrocarbyl radicals wherein one or more hydrogen atoms arereplaced by a halogen atom, hydrocarbyl-substituted metalloid radicalswherein the metalloid is selected from Group 14 of the Periodic Table ofthe Elements, and halogen radicals. Suitable hydrocarbyl andsubstituted-hydrocarbyl radicals used to form derivatives of thesubstituted, delocalized π-bonded group will contain from 1 to 20 carbonatoms and include straight and branched alkyl radicals, cyclichydrocarbon radicals, alkyl-substituted cyclic hydrocarbon radicals,aromatic radicals and alkyl-substituted aromatic radicals. In additiontwo or more such radicals may together form a fused ring system or ahydrogenated fused ring system. Examples of the latter are indenyl-,tetrahydroindenyl-, fluorenyl-, and octahydrofluorenyl- groups. Suitablehydrocarbyl-substituted organometalloid radicals include mono-, di- andtrisubstituted organometalloid radicals of Group 14 elements whereineach of the hydrocarbyl groups contains from 1 to 20 carbon atoms. Moreparticularly, suitable hydrocarbyl-substituted organometalloid radicalsinclude trimethylsilyl, triethylsilyl, ethyldimethylsilyl,methyldiethylsilyl, triphenylgermyl, trimethylgermyl and the like.

Substituted, delocalized π-bonded groups for use according to thepresent invention preferably are depicted by the formula: ##STR1##wherein: R' each occurrence is hydrogen or a moiety selected fromhalogen, alkyl, aryl, haloalkyl, alkoxy, aryloxy, silyl groups, andcombinations thereof of up to 20 non-hydrogen atoms, or two or more R'groups together form an aliphatic or aromatic fused ring system; and

R" (which is a divalent X group) is a group that is covalently bonded toM of the formula: --Z--Y--, wherein

Z is a divalent moiety comprising oxygen, boron, or a member of Group 14of the Periodic Table of the Elements; and

Y is a ligand group comprising nitrogen, phosphorus, oxygen or sulfur oroptionally Z and Y together form a fused ring system; Y is a linkinggroup covalently bonded to the metal comprising nitrogen, phosphorus,oxygen or sulfur, or optionally Z and Y together form a fused ringsystem.

In a highly preferred embodiment R" is: ##STR2## wherein: E eachoccurrence is carbon, silicon, or germanium;

q is an integer from 1 to 4;

Y' is nitrogen or phosphorous; and

R* each occurrence is hydrogen or a moiety selected from alkyl, aryl,silyl, halogenated alkyl, halogenated aryl groups and combinationsthereof having up to 20 non-hydrogen atoms,

R"' each occurrence is alkyl, aryl, silyl or a combination thereof (e.g.alkaryl, aralkyl, silylalkyl, etc.) having up to 10 carbon or siliconatoms; or

two or more R* groups or one or more R* groups and R'" together form afused ring system of up to 30 non-hydrogen atoms.

Highly preferred derivatives of a Group 4 or Lanthanide metal for useaccording to the invention correspond to the formula: ##STR3## wherein:M is zirconium or titanium;

Cp* is a cyclopentadienyl group; or a group selected from indenyl,fluorenyl and hydrogenated derivatives thereof; or one of the foregoinggroups substituted with one or more alkyl, aryl or cycloalkyl moietiesof up to 20 carbons, said Cp* further being bound in an η⁵ bonding modeto M and substituted by Z-Y;

Z is SIR*₂, CR*₂, SiR*₂ SiR*₂, CR*₂ CR*₂, CR*=CR*, CR*₂ SiR*₂, or GeR*₂;

Y is a nitrogen or phosphorus containing group corresponding to theformula --N(R"")-- or --P(R"")--;

wherein:

R* each occurrence is hydrogen or a moiety selected from alkyl, aryl,silyl, halogenated alkyl, halogenated aryl groups and combinationsthereof having up to 20 non-hydrogen atoms, and

R"" is C₁₋₁₀ alkyl or C₆₋₁₀ aryl,

X" each occurrence is halo, alkyl, aryl, alkoxy, or aryloxy of up to 20carbons; and

p is 2.

Examples of the above most highly preferred metal coordination compoundsinclude compounds wherein the R"" on the amido or phosphido group ismethyl, ethyl, propyl, butyl, pentyl, hexyl, (including branched andcyclic isomers), norbornyl, benzyl, or phenyl; Cp* is cyclopentadienyl,tetramethylcyclopentadienyl, indenyl, tetrahydroindenyl, fluorenyl,tetrahydrofluorenyl, octahydrofluorenyl, or one of the foregoing groupsfurther substituted with one or more methyl, ethyl, propyl, butyl,pentyl, hexyl, (including branched and cyclic isomers), norbornyl,benzyl, or phenyl groups; and X is methyl, neopentyl, trimethylsilyl,norbornyl, benzyl, methylbenzyl, phenyl, or pentafluorophenyl.

Illustrative derivatives of Group 4 or Lanthanide metals that may beemployed in the practice of the present invention include:hydrocarbyl-substituted monocyclopentadienyl compounds such as:

cyclopentadienylzirconiumtrimethyl,

cyclopentadienylzirconiumtriethyl,

cyclopentadienylzirconiumtripropyl,

cyclopentadienylzirconiumtriphenyl,

cyclopentadienylzirconiumtribenzyl,

cyclopentadienyltitaniumtrimethyl,

cyclopentadienyltitaniumtriethyl,

cyclopentadienyltitaniumtripropyl,

cyclopentadienyltitaniumtriphenyl,

cyclopentadienyltitaniumtribenzyl,

cyclopentadienylhafniumdi(p-tolyl),

cyclopentadienyltitanium-2,4-pentadienyl,

pentamethylcyclopentadienylzirconiumtrimethyl,

pentamethylcyclopentadienylzirconiumtriethyl,

pentamethylcyclopentadienyl-zirconiumtripropyl,

pentamethylcyclopentadienyl zirconiumtriphenyl,

pentamethylcyclopentadienyl zirconiumtribenzyl,

pentamethylcyclopentadienyltitaniumtrimethyl,

indenylzirconium trimethyl,

indenylzirconium triethyl,

tetrahydroindenylzirconiumtripropyl,

indenylzirconiumtriphenyl,

indenylzirconiumtribenzyl,

indenyltitaniumtrimethyl,

indenyltitaniumtriethyl,

indenyltitaniumtripropyl,

indenyltitaniumtriphenyl,

tetrahydroindenyltitaniumtribenzyl,

indenylhafniumdi(p-tolyl),

cyclopentadienyltitaniumtriethyl,

pentamethylcyclopentadienyltitaniumtripropyl,

cyclopentadienyltitaniumtriphenyl,

pentamethylcyclopentadienyltitaniumtribenzyl,

pentamethylcyclopentadienylzirconiumtribenzyl,

pentamethylcyclopentadienyllanthanumdi(tris(trimethyl silyl)methyl),etc.;

hydrocarbyloxy substituted compounds such as:

cyclopentadienyltitaniumtrimethoxide,

cyclopentadienyltitaniumtriisopropoxide,

cyclopentadienyltitaniumtriphenoxide,

cyclopentadienylzirconiumtrimethoxide,

cyclopentadienylzirconiumtriisopropoxide,

cyclopentadienylzirconiumtriphenoxide,

pentamethylcyclopentadienyltitaniumtrimethoxide,

pentamethylcyclopentadienyltitaniumtriisopropoxide,

pentamethylcyclopentadienyltitaniumtriphenoxide,

pentamethylcyclopentadienylzirconiumtrimethoxide,

pentamethylcyclopentadienylzirconiumtriisopropoxide,

pentamethylcyclopentadienylzirconiumtriphenoxide,

indenyltitaniumtrimethoxide,

tetrahydroindenyltitaniumtriisopropoxide,

indenyltitaniumtriphenoxide,

tetrahydroindenylzirconiumtrimethoxide,

indenylzirconiumtriisopropoxide,

fluorenylzirconiumtriphenoxide,

octahydrofluorenylzirconiumtriphenoxide,

octahydrofluorenyltitaniumtribenzoxide, etc.;

halo substituted compounds such as:

cyclopentadienylzirconiumtrichloride,

cyclopentadienyltitaniumtrichloride,

indenyltitanium trichloride,

pentamethylcyclopentadienyltitaniumtrichloride,

pentamethylcyclopentadienylhafniumtrichloride,

cyclopentadienylosmium dichloride, etc.;

and compounds comprising mixtures of substituents such as:

cyclopentadienyltitaniumdimethylisopropoxide,

pentamethylcyclopentadienylzirconiummethyldichloride,

cyclopentadienyllanthanumchloroisopropoxide,

cyclopentadienyltitanium(tert-butylamino)methylchloride,

indenyltitanium(tert-butylamino)dibenzyl,

[(N-tert-butylamido)dimethyl(η⁵-cyclopentadienyl)silane]zirconiumdibenzyl,

[(N-tert-butylamido)dimethyl(η⁵-cyclopentadienyl)silane]zirconiumdimethyl,

[(N-tert-butylamido)dimethyl(η⁵-cyclopentadienyl)silane]titaniumdibenzyl,

[(N-tert-butylamido)dimethyl(η⁵-cyclopentadienyl)silane]titaniumdimethyl,

[(N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane]zirconiumdibenzyl,

[(N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane]zirconiumdimethyl,

[(N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane]titaniumdibenzyl,

[(N-tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane]titaniumdimethyl,

[(N-tert-butylamido)dimethyl(η⁵ -indenyl)silane]zirconiumdibenzyl,

[(N-tert-butylamido)dimethyl(η⁵-tetrahydroindenyl)silane]zirconiumdimethyl,

[(N-phenylamido)dimethyl(tetramethyl-η⁵cyclopentadienyl)silane]titaniumdibenzyl,

[(N-tert-butylamido)dimethyl(η⁵ -fluorenyl)silane]titaniumdimethyl,

[(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2ethanediyl]dimethylzirconium,

[(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2ethanediyl]titaniumdibenzyl,

[(N-methylamido)(η⁵-cyclopentadienyl)-1,2-ethanediyl]zirconiumdibenzhydryl,

[(N-methylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2ethanediyl]titaniumdineopentyl,

[(phenylphosphido)(tetramethyl-η⁵-cyclopentadienyl)methylene]titaniumdiphenyl,

[(N-tert-butylamido)(di(trimethylsilyl))(tetramethyl-η⁵-cyclopentadienyl)silane]zirconiumdibenzyl,

[(N-benzylamido)(dimethyl)(η⁵-cyclopentadienyl)silane]titaniumdi(trimethylsilyl),

[(phenylphosphido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silane]zirconiumdibenzyl,

[(N-tert-butylamido)(dimethyl)(tetramethyl-η⁵-cyclopentadienyl)silane]hafniumdibenzyl,

[(tetramethyl-η⁵ -cyclopentadienyl)-1,2-ethanediyl]titaniumdibenzyl,

[2-η⁵-(tetramethylcyclopentadienyl)-1-methyl-ethanolato-(2-)]titaniumdibenzyl,

[2-η⁵-(tetramethylcyclopentadienyl)-1-methyl-ethanolato-(2-)]titaniumdimethyl,

[2-η⁵-(tetramethylcyclopentadienyl)-1-methyl-ethanolato-(2-)]zirconiumdibenzyl,

[2-η⁵-(tetramethylcyclopentadienyl)-1-methyl-ethanolato-(2-)]zirconiumdimethyl,

[2-[(4a, 4b, 8a, 9, 9a -η)-9-H-fluoren-9-yl]cyclohexanolato(2-)]titaniumdimethyl,

[2-[(4a, 4b, 8a, 9, 9a -η)-9-H-fluoren-9-yl]cyclohexanolato(2-)]titaniumdibenzyl,

[2-[(4a, 4b, 8a, 9, 9a -η)-9-H-fluoren-9-yl]cyclohexanolato(2-)]zirconiumdimethyl,

[2-[(4a, 4b, 8a, 9, 9a -η)-9-H-fluoren-9-yl]cyclohexanolato(2-)]zirconiumdibenzyl, and the like.

Other compounds which are useful in the preparation of catalystcompositions according to this invention, especially compoundscontaining other Group 4 or Lanthanide metals, will, of course, beapparent to those skilled in the art.

In the most preferred embodiment --Z--Y-- is an amidosilane oramidoalkane group of up to 10 nonhydrogen atoms, that is,(tert-butylamido)(dimethylsilyl) (tert-butylamido)-1-ethane-2-yl, etc.

Compounds useful as the second component in the preparation of thecompounds of this invention will comprise a stable carbonium ion, and acompatible noncoordinating anion. Examples include tropilliumtetrakispentafluorophenylborate, triphenylmethyliumtetrakispentafluorophenylborate, benzene(diazonium)tetrakispentafluorophenylborate, tropilliumphenyltrispentafluorophenylborate, triphenylmethyliumphenyltrispentafluorophenylborate, benzene(diazonium)phenyltrispentafluorophenylborate, tropilliumtetrakis(2,3,5,6-tetrafluorophenyl)borate, triphenylmethyliumtetrakis(2,3,5,6-tetrafluorophenyl)borate, benzene(diazonium)tetrakis(2,3,5,6-tetrafluorophenyl)borate, tropilliumtetrakis(3,4,5-trifluorophenyl)borate, triphenylmethyliumtetrakis(3,4,5-trifluorophenyl)borate, benzene(diazonium)tetrakis(3,4,5-trifluorophenyl)borate, tropilliumtetrakis(3,4,5-trifluorophenyl)aluminate, triphenylmethyliumtetrakis(3,4,5-trifluorophenyl)aluminate, benzene(diazonium)tetrakis(3,4,5-trifluorophenyl)aluminate, tropilliumtetrakis(1,2,2-trifluoroethenyl)borate, triphenylmethyliumtetrakis(1,2,2-trifluoroethenyl)borate, benzene(diazonium)tetrakis(1,2,2-trifluoroethenyl)borate, tropilliumtetrakis(2,3,4,5-tetrafluorophenyl)borate, triphenylmethyliumtetrakis(2,3,4,5-tetrafluorophenyl)borate, benzene(diazonium)tetrakis(2,3,4,5-tetrafluorophenyl)borate, etc.

Preferred compatible noncoordinating anions are those containing asingle coordination complex comprising a charge-bearing metal ormetalloid core which anion is relatively large (bulky), capable ofstabilizing the active catalyst species (the Group 3-10 or LanthanideSeries cation) which is formed when the two components are combined andsaid anion will be sufficiently labile to be displaced by olefinic,diolefinic and acetylenically unsaturated substrates or other neutralLewis bases such as ethers, nitriles and the like. Suitable metalsinclude, but are not limited to, aluminum, gold, platinum and the like.Suitable metalloids include, but are not limited to, boron, phosphorus,silicon and the like. Compounds containing anions which comprisecoordination complexes containing a single metal or metalloid atom are,of course, well known and many, particularly such compounds containing asingle boron atom in the anion portion, are available commercially. Inlight of this, salts containing anions comprising a coordination complexcontaining a single boron atom are preferred.

Preferred compatible non-coordinating anions aretetrakis(pentafluorophenyl)borate, tetrakis(2,3,5,6-tetrafluorophenyl)borate,tetrakis(2,3,4,5-tetrafluorophenyl)borate,tetrakis(3,4,5-trifluorophenyl)borate,tetrakis(1,2,2-trifluoroethenyl)borate, andphenyltris(perfluorophenyl)borate.

In a most preferred embodiment of the present invention C_(p) *--Z--Y--Mis (tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silanetitanium, n is two, X is methyl or benzyl, andA⁻ is tetrakispentafluorophenyl borate.

With respect to the combination of first, metal containing component andcarbonium salt to form a catalyst according to this invention, it shouldbe noted that the two components must be selected so as to avoidtransfer of a fragment of the anion, particularly an aryl group, or afluorine or hydrogen atom to the metal cation, thereby forming acatalytically inactive species. This could be done by steric hindrance,resulting from substitutions on the cyclopentadienyl carbon atoms aswell as substitutions on the aromatic carbon atoms of the anion. Itfollows that first components comprising perhydrocarbyl-substitutedcyclopentadienyl radicals could be effectively used with a broader rangeof second compounds than could first components comprising unsubstitutedcyclopentadienyl radicals. As the amount and size of the substitutionson the cyclopentadienyl radicals are reduced, however, more effectivecatalysts are obtained with second compounds containing anions which aremore resistant to degradation, such as those with substituents on theortho positions of the phenyl rings. Another means of rendering theanion more resistant to degradation is afforded by fluorinesubstitution, especially perfluoro-substitution, in the anion.Fluoro-substituted stabilizing anions may, then, be used with a broaderrange of first components.

The chemical reactions which occur in forming the catalysts of thisinvention may, when a preferred, boron containing compound is used asthe second component, be represented by reference to the general formulaset forth herein as follows:

    LMX.sub.m X'.sub.n X".sub.p+1 +©.sup.+ [BQ.sub.4].sup.- →[LMX.sub.m X'.sub.n X".sub.p ].sup.+ [BQ.sub.4 ].sup.- +©X"

wherein L, M, X', X", X, m, n, p and ©+ have the previously identifiedmeanings, ©X" is the neutral remnant of the carbonium ion, and Q ispentafluorophenyl.

In general, the stability of the neutral remnant of the carbonium ioncauses the reaction to be driven to completion thereby resulting inincreased yields of the desired cationic catalyst. Accordingly theresulting catalysts are extremely active and effective polymerizationcatalysts.

In general, the catalyst can be prepared by combining the two componentsin a suitable solvent at a temperature within the range from about -100°C. to about 300° C. The catalyst may be separately prepared prior to useby combining the respective components or prepared in situ bycombination in the presence of the monomers to be polymerized. It ispreferred to form the catalyst in situ due to the exceptionally highcatalytic effectiveness of catalysts prepared in this manner. While thecatalysts may not contain pyrophoric species, the catalysts' componentsare sensitive to both moisture and oxygen and should be handled andtransferred in an inert atmosphere such as nitrogen, argon or helium.

The catalyst may be used to polymerize α-olefins and/or acetylenicallyunsaturated monomers having from 2 to about 18 carbon atoms and/ordiolefins having from 4 to about 18 carbon atoms either alone or incombination. The catalyst may also be used to polymerize α-olefins,diolefins an/or acetylenically unsaturated monomers in combination withother unsaturated monomers. In a preferred embodiment the catalysts areemployed to prepare copolymers of mixtures of vinyl aromatic monomerswith olefins other than a vinyl aromatic monomer, specificallycopolymers of styrene with ethylene or propylene. In general, thepolymerization may be accomplished at conditions well known in the priorart.

Suitable solvents or diluents for the catalyst preparation andpolymerization include any of the solvents known in the prior art to beuseful as solvents in the polymerization of olefins, diolefins andacetylenically unsaturated monomers. Suitable solvents include, but arenot necessarily limited to straight and branched-chain hydrocarbons suchas isobutane, butane, pentane, hexane, heptane, octane and the like;cyclic and alicyclic hydrocarbons such cyclohexane, cycloheptane,methylcyclohexane, methylcycloheptane and the like and aromatic andalkyl-substituted aromatic compounds such as benzene, toluene, xyleneand the like. Suitable solvents also include liquid olefins which mayact as monomers or comonomers including ethylene, propylene, butadiene,cyclopentene, 1-hexane, 3-methyl-1-pentene, 4-methyl-1-pentene,1,4-hexadiene, 1-octene, 1-decene, styrene, and the like.

In a preferred embodiment, the catalyst is used to polymerize one ormore C₂ -C₈ α-olefins particularly ethylene or propylene, mostpreferably ethylene, at a temperature within the range from 0° C. to300° C., preferably 25° C. to 200° C. and at a pressure within the rangefrom atmospheric to 1000 psig (7MPa) preferably 15 to 700 psig (0.1-4.9MPa). In a most preferred embodiment of the present invention, thecatalyst will be used either to homopolymerize ethylene or tocopolymerize ethylene with a C₃ -C₈ α-olefin (including styrene) therebyyielding a copolymer. In both the preferred and most preferredembodiments, the monomers will be maintained at polymerizationconditions for a nominal holding time within the range from about 1 toabout 60 minutes and the catalyst will be used at a concentration withinthe range from about 10⁻⁸ to about 10⁻¹ moles per mole of monomer.

Having thus broadly described the present invention it is believed thatthe same will become even more apparent by reference to the followingexamples. It will be appreciated, however, that the examples arepresented solely for the purpose of illustration and should not beconstrued as limiting the invention.

EXAMPLE 1 (Tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silanetitaniumdimethyl and triphenylmethyliumtetrakis-pentafluorophenyl borate

(Tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silanetitaniumdimethyl was prepared by reaction ofmethyllithium and the corresponding metal dichloride complex, which inturn was prepared by reaction of lithium1,2,3,4-tetramethylcyclopentadienide with(N-t-butylamino)(dimethyl)silane chloride, followed by conversion to thedilithium salt, reaction with TiCl₃ to form the closed ring structure(N-t-butylamido)dimethyl(tetramethyl-η⁵ -cyclopentadienyl)titaniumchloride, and oxidation of the metal center with methylene chloride toform (N-t-butylamido)dimethyl(tetramethyl-η⁵ -cyclopentadienyl)titaniumdichloride.

A glass vial was charged with 41 mg of (tert-butylamido)(dimethyl)(η⁵-tetramethylcyclopentadienyl)silanetitanium dimethyl, 0.124 mmol) and114 mg of triphenylmethylium tetrakis-pentafluorophenyl borate.Approximately 1 mL of d⁸ -toluene was added and the vial was shakenvigorously for about 5 minutes. A dark red-brown oil separated to thebottom of the vial leaving a pale orange solution above. Analysis of thepale orange solution by ¹ H and ¹³ C NMR indicated the presence of1,1,1-triphenylethane.

Polymerization 1

A 2 L Parr reactor was charged with 828 g of mixed hexanes solvent(Isopar™ E, available from Exxon Chemicals, Inc.) followed by 30 g of1-octene. The reactor was heated to 150° C. and pressurized withethylene to 500 psig (3.55 MPa). 25 Δpsi (0.17 ΔMPa) hydrogen chaincontrol agent was then expanded into the reactor from a 75 ml hydrogenexpansion tank. After several minutes, 2 mmole oftert-butylamido)dimethyl(tetramethyl-η⁵ -cyclopentadienyl)silanetitaniumdimethyl and 2 mmole of triphenylmethylium tetrakispentafluorophenylborate (catalyst/cocatalyst) in toluene were pre-contacted and added tothe reactor via a transfer line from a dry box. Upon addition of themetal complex/cocatalyst mixture to the reactor, a 25.5° C. exotherm wasobserved. After 9 min. the reaction was stopped and an antioxidant(Irganox™-1010, available from Ciba-Geigy, Inc.) was added to thepolymer solution. The polymer was then dried to constant weight in avacuum oven. 53.8 g. of an ethylene/octene copolymer having a melt indexof 0.985 was obtained.

Polymerization 2

A 2 L Parr reactor was charged with 740 g of Isopar™ E followed by 118 gof 1-octene. The reactor was heated to 140° C. and pressurized withethylene to 500 psig (3.55 MPa). 25 Δpsi (0.17 ΔMPa) hydrogen chaincontrol agent was then expanded into the reactor. After several minutes,2 mmole of tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silanetitanium dimethyl and 2 mmole oftriphenylmethylium tetrakispentafluorophenyl borate(catalyst/cocatalyst) in toluene were pre-contacted and added to thereactor via a transfer line from a dry box. Upon addition of thecatalyst/cocatalyst mixture to the reactor, a 5.5° C. exotherm wasobserved. After 15 min. the reaction was stopped and an antioxidant(Irganox-1010, available from Ciba-Geigy, Inc.) was added to the polymersolution. The polymer was then dried to constant weight in a vacuumoven. 24.0 g. of an ethylene/octene copolymer having a melt index of0.626 was obtained.

EXAMPLE 2

The reaction conditions of Example 1 were substantially repeated using0.5 μmoles of the metal complex and 0.5 μmoles of the carbonium salteach in 2 ml toluene solution to prepare the catalyst/cocatalyst insitu. The reaction temperature was 140° C. Upon addition of thecocatalyst to the reactor, a 17.9° C. exotherm was observed. After 15min. the reaction was stopped and the polymer solution was charged to areceiver containing 100 mg Irganox 1010 and 10 ml isopropanol to killthe catalyst. The polymer was then dried to constant weight in a vacuumoven. Yield was 69.2 g. of an ethylene/octene copolymer having a meltindex of 7.2.

EXAMPLE 3

The reaction conditions of Example 1 were substantially repeated.Accordingly, a 2 L Parr reactor was charged with 788 g of Isopar™ Efollowed by 70 g of 1-octene. The reactor was heated to 120° C. andpressurized with ethylene to 500 psig (3.55 MPa). 38 Δpsi (0.17 ΔMPa)hydrogen chain control agent was then expanded into the reactor. Afterseveral minutes, 1 μmole oftert-butylamido)dimethyl(tetrahydrofluorenyl)silanetitanium dimethyl(prepared in analogous manner to the metal complex of Example 1) in 2 mltoluene solution followed by 1 μmole of triphenylmethyliumtetrakispentafluorophenyl borate in 2 ml toluene solution were added tothe reactor. Upon addition of the cocatalyst to the reactor, a 34.9° C.exotherm was observed. After 15 min. the reaction was stopped and thepolymer solution was charged to a receiver containing 100 mg Irganox1010 and 10 ml isopropanol to kill the catalyst. The polymer was thendried to constant weight in a vacuum oven. Yield was 78.6 g. of anethylene/octene copolymer having a melt index of 0.62.

What is claimed is:
 1. An addition polymerization process wherein one ormore addition polymerizable monomers are polymerized in the presence ofa catalyst prepared by a process comprising contactinga) a derivative ofa Group 4 or Lanthanide metal corresponding to the formula: ##STR4##wherein: M is zirconium or titanium; Cp* is a cyclopentadienyl group; ora group selected from indenyl, fluorenyl and hydrogenated derivativesthereof; or one of the foregoing groups substituted with one or morealkyl, aryl or cycloalkyl moleties of up to 20 carbons, said Cp* furtherbeing bound in an η⁵ bonding mode to M; Z is SIR*₂, CR*₂, SiR*₂ SiR*₂,CR*₂ CR*₂, CR*=CR*, CR*₂ SiR*₂, or GeR*₂. Y is a nitrogen or phosphoruscontaining group corresponding to the formula --N(R"")-- or--P(R"")--;wherein: R* each occurrence is hydrogen or a moiety selectedfrom alkyl, aryl, silyl, halogenated alkyl, halogenated aryl groups andcombinations thereof having up to 20 non-hydrogen atoms, and R"" isC₁₋₁₀ alkyl or C₆₋₁₀ aryl; X" each occurrence is halo, alkyl, aryl,alkoxy, or aryloxy of up to 20 carbons; and p is 2, with b) a saltcorresponding to the formula ©+A-, wherein ©+ is a stable carbonium ioncontaining up to 30 nonhydrogen atoms and A- is a noncoordinatingcompatible anion; under conditions to cause abstraction of one X" andformation of the neutral species, ©X".
 2. A process according to claim1, wherein ©⁺ is triphenylmethylium or tropylium.
 3. A process accordingto claim 1, wherein the catalyst is prepared in situ.
 4. A processaccording to claim 1 wherein X" is methyl or benzyl.
 5. A processaccording to claim 1 wherein A⁻ is tetrakis(pentafluorophenyl)borate.